When a Splitter contains both RadPanes with size in percent and free-sized panes, the width of the fomer is calculated properly only after the initial loading and remains the same the the page is resized.
Steps to reproduce:
1. <telerik:RadSplitter ID="RadSplitter1" runat="server" Width="100%">
<telerik:RadPane ID="RadPane1" runat="server" Width="10%"></telerik:RadPane>
<telerik:RadSplitBar ID="RadSplitbar1" runat="server" ></telerik:RadSplitBar>
<telerik:RadPane ID="RadPane2" runat="server"></telerik:RadPane>
</telerik:RadSplitter>
2. Resize the browser.
Result: the size of RadPane1 is not recalculated
Temporary workaround:
Set size in perncent to all RadPanes in the Splitter.